Door operators occasionally include a sensor which detects the angular position of a door during opening and closing events. Conventional door operators of this type often sense door position through the use of a potentiometer or a relative optical encoder, each of which may have certain limitations. For example, potentiometers typically have a relatively short life span due to the fact that the mechanical interface between the wiper and the resistive material causes the elements to wear. Additionally, many optical encoders require a constant power supply, and a power loss will cause the controller to reset an internal counter used to determine the position of the door. As a result, such systems may require recalibration after a power failure event. Therefore, a need remains for further improvements in this technological field.